An investigative group in Britain says it has identified one of the two suspects in the poisoning of an ex-Russian spy in the U.K. as a highly-decorated colonel in the Russian military intelligence agency GRU.

The group, Bellingcat, said Wednesday that the suspect, whose passport name was Ruslan Boshirov, is in fact Col. Anatoliy Chepiga, who in 2014 was awarded Russia's highest medal, the Hero of Russia.

Britain has charged Boshirov and another suspect, Alexander Petrov, with trying to kill Russian ex-spy Sergei Skripal and his daughter on March 4 with the Soviet-designed nerve agent Novichok in the English city of Salisbury. Britain has said the attack received approval "at a senior level of the Russian state," an accusation Moscow has fiercely denied.

There was no immediate comment from Moscow on Bellingcat's latest claim.

The two Russian men have appeared on the state-funded RT channel, saying they visited Salisbury as tourists and had nothing to do with the Skripal poisoning. They denied the British claim that they were Russian military intelligence officers, saying they work in the nutritional supplements business.

Bellingcat said it perused pictures of graduates of Russian military academies and found a man resembling Boshirov in a group shot. It then narrowed its search to one military officer, Chepiga, using leaked Russian databases available on the internet. The group eventually tracked down Chepiga's passport file, dated 2003, with a picture bearing a strong resemblance to Boshirov.

It said Chepiga served several stints in Chechnya, where Russian forces were fighting Islamic rebels. The group noted that the officer was decorated with the Hero of Russia medal in December 2014, signaling that he likely received the high award for his actions in eastern Ukraine.